It's a behind-the-scenes photo taken by Joseph Malozzi, but it IS from s5e11, that scene.
I believe it's from a deleted scene from s5e11 The Lost Tribe.
spoiler
The Lost Tribe of Asgard show up, the Aterro Device gets activated, Todd steals the Daedalus to destroy the facility it's contained in, Ronon and Dr. Keller are the only ones who don't get captured, and right around the 30 minute mark, they all bust into the bridge to find it deserted. Keller by this point has already killed a few wraith drones with her p90, and Woolsey has a larger assault rifle. There are multiple people with them stacked up for a breach, who we don't see in the screenshot, but I vaguely remember a few deleted scenes from the dvds and this is the only time I'm aware we see Keller and Woolsey together with guns.